IT has a million-dollar title, a score that defined an era, hefty advance ticket sales and a producer with an unfailing instinct for what the public wants.

Can anything stop “Saturday Night Fever,” the disco juggernaut that’s headed to Broadway in the fall?

Probably not.

The show, already a hit in London, is shaping up to be the blockbuster of the 1998-99 season.

Its producer is Robert Stigwood, the fabled Australian impresario behind the Bee Gees, the Broadway hit “Evita” and the 1977 movie “Saturday Night Fever” on which his new musical is based.

Scheduled to open Oct. 21 at the Minskoff Theater, “Saturday Night Fever” has already racked up advance ticket sales of nearly $12 million. A single ad in The New York Times last spring pulled in $500,000 alone, production sources say.

Those are impressive numbers that bode well for a show’s future. Still, nothing is ever a slam-dunk on Broadway, where high costs, critical sniping and poisonous word-of-mouth can turn a seemingly sure-fire hit into a flop.

Two recent examples are “Sunset Boulevard” and “Victor/Victoria.” Both opened with enorumous hype and huge advances – $30 million for “Sunset,” $15 million for “Victor” – but wound up closing in the red.

What, if anything, could prevent “Saturday Night Fever” from turning a profit?

For starters, it may not be very good. London critics trashed the show, and it’s a fair bet New York reviewers will do the same. Broadway insiders are also bad-mouthing the musical (envy is probably a factor here), saying that it makes “Footloose” look like “My Fair Lady.”

The critical barrage did not stop the show from becoming a hit in London. But New York critics have considerably more influence than their London counterparts, and their attacks could draw blood.

Worse, bad reviews could reinforce bad word-of-mouth.

“The $12 million advance will make the show critic-proof for six months,” says a person connected to the show. “After that, it’s marketing, advertising and whether or not people like it.”

Production sources say Stigwood is confident New Yorkers will respond to the show the same way Londoners did. For a while, he refused to let director Arlene Phillips make any changes, even though she felt the show needed work.

But the producer, according to a recent Wall Street Journal profile, is ailing and is not as hands-on as he was during the London run.

In his absence, production sources say Phillips has been able to exert more control, giving the show a rougher, more dramatic edge than it has in London.

Bookwriter Nan Knighton is also said to be polishing her script, which many critics found laughably inept (in one scene, the main character breaks up a fight at the disco and says, by way of a song cue, “We shouldn’t be fighting! We should be dancing!”).

Another potential problem for “Saturday Night Fever” is its high cost. In London, the price tag was $6.5 million. The New York production is budgeted at almost $10 million.

The show will also have a weekly overhead of $500,000, theater people say – almost twice what it cost to run in London.

If it sells out, “Saturday Night Fever” could conceivably be in the black within a year-and-a-half. But if bad reviews and poor word-of-mouth take a toll, the show could be forced to dip into its advance.

“You can use up your advance very quickly if your’re losing money early on,” says veteran Broadway producer James Freydberg.

Because of its A-list title, “Saturday Night Fever” doesn’t need a star to sell tickets. Still, it comes to New York minus its chief asset in London: Adam Garcia.

The charismatic young actor became a genuine sensation playing Tony Manero (John Travolta in the movie). Hordes of teenage girls waited for him outside the stage door and, according to press reports, visited the show several times to watch him swivel his hips.

Garcia opted not to come to Broadway, reportedly because Stigwood would not meet his salary demands.

That’s a loss for the show, which would have benefited from the publicity Garcia would have generated on Broadway.

A nationwide search for a new Tony Manero yielded James Carpinello, who starred in the off-Broadway play “Stupid Kids” last season.

Stigwood, a master promoter, will certainly put his publicity machine behind Carpinello. But whether the actor can catch fire the way Garcia did is very much up in the air.

And what of the audience for “Saturday Night Fever”? In London, it was predominantly working class – the kinds of folks who flock to such long-running West End shows as “Buddy” and “Blood Brothers.”

In New York, “Saturday Night Fever” will probably lure the bridge-and-tunnel crowd that turned “Grease” and “Smokey Joe’s Cafe” into hits.

But, to make back $10 million, it will also have to attract more sophisticated theatergoers who might be put off by bad reviews.

Here, fond memories of the ’70s – which cut across class lines – may come into play.

Ronald Lee, president Group Sales Box Office in New York, a group sales ticket agency, says his upscale customers who normally buy shows like “Kiss Me, Kate” are also clamoring for “Saturday Night Fever.”

“To my surprise, I am selling ‘Saturday Night Fever’ to the traditional theatergoer,” he says. “I don’t know if it’s nostalgia for the film or the music. I only know that people want it.”